Earth Almanac: July/September 2002

Flue Fliers

At twilight a black funnel cloud forms in a windless and otherwise unblemished sky. But instead of sucking up the building over which it hovers, the building sucks it down until only a few wisps, swirling like candle soot, fade into the gathering darkness. Swifts, massing for fall migration, have dropped into their night roost in an unused chimney. In the Northwest the species is Vaux's swift; east of the Rockies it's the chimney swift. Both are often the victims of chimney sweeps or of fires kindled by people who don't know the birds are there. Swifts, related to hummingbirds, have cigar-shaped bodies; long, narrow wings; and feet so puny they can only cling to vertical surfaces. Wings quivering, large mouths agape, they orbit parks, fields, and backyards, describing wild loops, chipping loudly. During the day they live in the air, eating, bathing, copulating, gathering nesting materials, and possibly sleeping on the wing. If you have swifts roosting or nesting in your chimney, close the damper to keep the birds from falling into the fireplace. Despite the oft-told wives' tale, nests pose no fire hazard, and removing them is a violation of the Migratory Bird Treaty Act. If you don't have a chimney and want swifts, you can set up a swift tower. For plans, log on to www.tpwd.state.tx.us/nature/birding/chimneyswift. 

Meet Your Skinks

Now, when they are seeking winter dens in logs, mammal burrows, woodpiles, and stonewalls, is the best time to meet neighbors you may not have known you had. If you live east of the Great Plains and outside northern New England, your state probably hosts five-lined skinks. Some five-lined skinks indeed have five lines—from neck to mid-tail. But others, particularly older ones, do not. The head of the adult male is redder than the female's. When a male sees another five-lined skink, he charges with his mouth wide open; if the stranger turns out to be a rival male, a fight ensues. Juveniles have bright-blue tails, presumably to decoy natural enemies away from vital body parts. When a predator or person grabs the tail, it detaches, then wiggles seductively. Sphincter muscles in the stump close off the caudal artery, thereby preventing excessive blood loss. The lizard then grows a new tail, but one with different scales and more subdued coloration.

Fragrance of Indian Summer

There is a pause between summer and fall, when nights are cool and full of cricket song, when swamp maples blush, and when limbs along the meadow's edge bend low with fruit. Among the first of these fruits to ripen are wild grapes—about 30 species throughout our nation, mostly native and often natural hybrids. Wild grapes feed a host of wildlife, including bears, foxes, skunks, opossums, doves, grouse, quail, wild turkeys, prairie chickens, woodland thrushes, woodpeckers, cardinals, and at least 100 other songbirds. The fragrance of wild grapes carries so far and is so unmistakable that the best way to find them is with your nose. There are plenty for everybody, so don't hesitate to pick some; their tartness makes them perfect for jelly.